SLIDE 2 A brief history
Sir Sandford Fleming
Scotland born Canadian Sir Sandford Fleming developed the Time Zones after missing his train.
Trains
What would happen if trains traveling along a shared track had different times?
GMT
Greenwich Mean Time (GMT)
- riginally known as the “mean
solar time” at the Royal Observatory in Greenwich, London, which later became adopted as a Universal time standard (UT) What runs through Greenwich?
In Summary
- Since the late 19th century, the Prime Meridian at Greenwich has
been the reference point for GMT.
- Before this, towns around the kept its own local time (Examples
in previous video)
- When railways and communication networks expanded there was
an urgent need around the world for international time standards.
- Learn more at https://goo.gl/1WGkTV
Universal Time
- The Prime Meridian marks the middle of a Time Zone that marks Universal
Time (UT).
- Remember that each time zone extends 15 degrees.
- That means there are 7.5 degrees on each side of the Prime Meridian.
- Time in other zones is compared to the UT.
7.5 degrees 7.5 degrees
How do Time Zones work?
The earth rotates from east to west. Sun rises in the East and sets in the West. Time Zones that are east of the Prime Meridian are Ahead of the UT. Times Zones that are west of the Prime Meridian are Behind the UT Some countries change the shape of their time zone. Newfoundland has a half hour time zone because St John’s sits on a time zone line.
International Date Line
Created because Sailors going around the earth arrived home a day ahead or behind those who stayed behind. It follows the 180 degree line of Longitude This line zig-zags to landmases or groups of islands. If you cross the date line going west = you add a day If you cross the date line going east = you loss a day
